Sparking plug.



PATEiITED AUG. 28, 1906.

C. E. ROSS.

SPARKING PLUG, urmounon FILED JULY 9 1904.

wnnissis l citizen of the United States, residing UNITED STATES PATENT OFFICE.

Specification of Letters Patent.

Patented 'Aug. 28, 1906.

Application fllotl July 8, 1904, Serial No. 216,369.

To all whom it may concern: =Be it known that I, CHARLES E. Ross,- a

at Crafton, in the county of Allegheny an State of Pennsylvania, haveinvented or discovered new and useful Improvements in Sparking Plugs, of which thefollowing is a specification.

In the accompanying drawings, Fi ure 1 is a lon itudinal section of my improve sparking pug. Fig. 2 isza crdss-section of the same along theline II II in 1 looking in the direction of the arrow, whl c Fig. 3 is an enlarged perspective of my detachable cover.

My invention consists generally in certain novel improvements in electric sparking plugs for use in connection with gas engines or motors. extend into the cylin er of the en ines, and by the spark producedthereby tie gas or other power medium is ignited in the cylinder. A reatdrawback to the proper operation of t ese devices has been the deposit of" soot or other products of combustion on the exposed extremity of the plug, which must be frequently cleansed to produce. satisfactory operation. As a reventive of such deposits covers are enera ly provided which are intended to s ield the plug end from such deposits; but while in a measure preventing said deposits the covers themselves have acted as an impediment to the proper cleansing of the plug end, and therefore in a measure increase the fault that they are intended to prevent.

I have devised a detachable cover which not only protects the plug to a large degree from a de osit of objectionable matter, but also may e readily removed for the proper cleansing of the sparking plu I also so construct m cover that it aso acts as a ground-pole i 01 the sparking mechanism, thus simplif mg and cheapcning the manufacture" thereo The following is a detailed description of my invention, reference being had to the accompanying drawings, which make part of this specification.

1 1 represent portions of the wall of a cylinder of a gas engine or motor of an Y ty e. 2 is an aperture in the wall of said cylinder, prefera ly annular, reinforced by an integral collar 3, which is internall threaded to engage the threaded end of p ug-casing 4. 5 is an externally-squared portion of said plug Such plugs are attached to and casing means of which a wrench may be applied or screwin in it place.

6 is a packing c any suitable character, which is compressed between the outer edge of collar 3 and annular shoulder 4- on casing 4, thus preventing the escape of as from the cylinder between the collar and t e casing 7 1s a core, usually constructed of porcelain or similar non-conducting material, which is seated. in thdxb'ore of the hollow casin 4 and whose inner extremity protrudes slight y from said casing, as shown in Fig. l. The bore of said casing is enlarged some distance from the inner end, forming an annular shoulder 8, between which and the annular shoulder 9 on core 7 a packing 10 is compressed, thus reventin the escape of gas from the cylin erithrougfi the bore of the casing. The core 7 is retained in place in the casingb means oflock-nut 11, which by means 0 its exterior threaded portion l2 engages the interior threaded portion 13 of the casing 4, which also by means of its inner end abuts against shoulder 14 of the core 7.

15 is the electrode-rod, suitably connected to the source of electric current (not shown) and passing through a central longitudinal aperture in said core 4.

16 is a cap which engages the outer end of core 7 and holds the rod 15 firmly seated in place and also prevents escape of gas.

The inner extremit is somewhat enlarged annular grdove 17. i l

18 is a cover, preferably stamped outjof a sheetof sprin metal, consisting of a circular plate :19 and egs 20 20, said le S being provided with outwardly-exten ing feet or flanges 21 21.

22 is a boss or projection, preferably struck up from the metal of the cover, which when t e cover is in place on the plug is directly opposite to the sparkin' end of rod 15, thus forming the ground cm? of the s arking are. To place the cover on the plug t e legs 20 20 are sprung together slightl with the fingers and the cover pressed on t is end of the lug until the feet 2; 21 spring out into an en gage the groove 17 in the casing, as shown in ig. 1, thus firmly securing the cover in place to protect the extremit of the sparking plug. To remove the cover, a 1 that is required is to spring the legs 20 20 slightly together,-so that t e feet 21 21 are disenga ed from the groove 17, and the cover may i e drawn from the of the bore of easing L assu throu h the legs 20 20 to the lug. It is evident, therefore, that the cover not only protects the plug end from a deposit of products of combustion of the gas, but also may readily be-removed, so that the lug end may be cleaned without difficulty. he ourrent passing down through. rod 15 would jump or spark across to boss 22 and thence ground, whic' is usually the motor or engine itself, or in case of a stationary engine ma be the earth itself.

It is evident that the legs ma be made separate from the cover and attac ed thereto by any convenient means as desired, as by rivets, for example. The boss may also be made separate and attached to the cover and ma be connected in any other manner wit the ground, as by a wire; but I prefer the construction shown as the most simple and inexpensive.

Many variations of details will occur to the skilled observer, which, however, are within the, purview of my invention.

Although for the sake of clearness 1 have minutely described the acconipanvin drawings, I do not wish to limit myself thereby, but claim, broadly In an electric sparkin mechanism, a ho]- low conducting-easin aving an annular groove in the mternai periphery thereof, a core of non-conducting material engagin said casing, an electrode-rod passin througl i said core and a detachable cover 0' stamped 'spring metaladapted to protect the ex osed end of said core and having integra legs adapted to be sprung into and engage said.

, groove, said cover forming one of the electrodes of said mechanism, substantially as and for the purpose set forth.

Signed at Pittshurg, Pennsylvania, this 6th day of July, 1904.

CHARLES E. ROSS.

Witnesses:

EDWARD A. LAURENCE, A. M. STEEN. 

